A laryngoscope is used by a medical professional for procedures that require access to a patient's larynx. One such procedure is intubating the trachea in order to assist or restore a patient's ability to breath. Intubation is performed during surgery, and the ability to intubate a patient rapidly in an emergency is very important.
A conventional laryngoscope has substantially a straight blade. When using a straight-blade laryngoscope to assist in an intubation procedure a physician must insert the laryngoscope blade so that the upper front teeth, the base of the tongue and the larynx of the patient are in a straight line. Only then can the physician directly see the larynx through which intubation is effected. Many patients have low mobility in the head and neck region while others have anatomical variations that prevent a straight line alignment of the upper front teeth, tongue base and larynx and intubating such patients is very difficult because the larynx cannot be seen.
Laryngoscopes fitted with fiberoptic bundles are known. Such laryngoscopes permit a physician to view the larynx even in difficult alignment situations. However, even when a patient's larynx is visible it is sometimes difficult to align the flexible endotracheal tube with the larynx opening and to insert the flexible tube through the larynx. Sometimes a stylet or forceps must be used to guide the tube and the use of such instruments frequently causes injury to the patient.
U.S. Pat. No. 4,982,729 issued to Tzu-Lang Wu discloses a laryngoscope that is a great improvement over the laryngoscopes described above. The laryngoscope of the Wu patent includes a curved blade attached to a handle at a convenient angle, the curved blade comprising two parts connected in bivalve fashion to be assembled before insertion into the patient's mouth. The interconnected bivalve elements can be disconnected within the patient's throat after intubation has been effected so that the laryngoscope can be removed from the patient in two pieces leaving the endotracheal tube in place. The laryngoscope of the Wu patent may or may not have fiberoptic bundles to provide light and a view of the area of the patient's larynx, and when such bundles are used they must be permanently connected to the blade of the laryngoscope. Accordingly, each laryngoscope blade must have its own dedicated fiberoptic bundles, and fiberoptic bundles are by far the most expensive element of a laryngoscope.
Each facility using a laryngoscope must have a number of blades available in different sizes. A large adult takes a different size blade than a small adult takes, and pediatric sized laryngoscope blades cannot be used for adult patients. The fiberoptic bundles used with the laryngoscopes disclosed in the Wu patent occupy space within the laryngoscope blade in the vertical direction which clutters the interior of the laryngoscope, thus requiring greater vertical dimension in order to pass an endotracheal tube through the laryngoscope. The vertical dimension of a laryngoscope blade is most critical and desirably it is as small as possible.
Fiberoptic bundles should be positioned so that loose tissue or an unduly relaxed epiglottis cannot block the light provided by a fiberoptic bundle or obscure the user's view of a patient's larynx.